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91.
Diet and cancer prevention: the fiber first diet   总被引:3,自引:0,他引:3  
Diet can play a major role in cancer prevention. The international differences in cancer incidence are largely accounted for by lifestyle practices that include nutrition, exercise, and alcohol and tobacco use. About 50% of cancer incidence and 35% of cancer mortality in the U.S., represented by cancers of the breast, prostate, pancreas, ovary, endometrium, and colon, are associated with Western dietary habits. Cancer of the stomach, currently a major disease in the Far East, relates to distinct, specific nutritional elements such as excessive salt intake. For these cancers, information is available on possible initiating genotoxic factors, promoting elements, and prophylactic agents. In general, the typical diet in the United States contains low levels of the potent carcinogenic agents, heterocyclic amines, formed during the cooking of meats. It provides only about half the potent appropriate fiber intake and is high in calories. About twice as many calories as would be desirable come from fat, certain kinds of which enhance the development of cancers. Other foods with functional properties, such as soy products and tea, can be beneficial. To achieve reduction in risk of certain cancers, diet must be optimized, primarily to reduce caloric intake and the fat component. The latter should be 20% or less of total caloric intake and fiber should be increased to 25- 35 g per day for adults. One approach to achieving these goals is the Fiber First Diet, a diet designed around adequate fiber intake from grains, especially cereals, vegetables, legumes, and fruits, which thereby reduces both calorie and fat intake. Such dietary improvements will not only reduce cancer and other chronic disease risks, but will contribute to a healthy life to an advanced age. A corollary benefit is a lower cost of medical care.   相似文献   
92.
A controlled trial of elective intervention with continuous inflating pressure (CIP) was performed in infants with severe hyaline membrane disease who weighed more than 1000 g at birth. Infants entered the trial if their arterial oxygen tension (PaO2) fell below 60 mmHg while breathing a fractional inspired oxygen concentration (F1O2) greater than 0-95. 11 out of 12 infants in the CIP-treated group and 10 out of 12 in the control group survived. 7 treated and 6 control infants required mechanical ventilation. When CIP was started the Pao2 of the treated infants increased, and they breathed high concentrations of oxygen for a significantly shorter period than the control infants. During the 31-month duration of the trial 107 other infants with severe hyaline membrane disease were admitted who did not meet the criteria for entry to the trial. 37 survived after breathing high concentrations of oxygen (F1O2 greater than 0-60) spontaneously without any ventilatory assistance, and the remaining 70 infants were already being ventilated on their arrival in the unit, usually because they had required mechanical ventilation during transfer from other hospitals. The neonatal survival rate for those infants born in this hospital during the study period was 88% (50 out of 57 infants) and for those referred from other hospitals it was 69% (51 out of 74 infants). The maximum further increase in overall survival rate that might have been achieved in our population of infants if CIP had been initiated very early in the course of the illness was 5%--i.e. from 77% (101/131) to 82% (107/131).  相似文献   
93.
The purpose of this study was to test whether brain laterality influences spontaneous recovery of hand motor function after controlled brain injuries to arm areas of M1 and lateral premotor cortex (LPMC) of the hemisphere contralateral to the preferred hand in rhesus monkeys. We hypothesized that monkeys with stronger hand preference would exhibit poorer recovery of skilled hand use after such brain injury. Degree of handedness was assessed using a standard dexterity board task in which subjects could use either hand to retrieve small food pellets. Fine hand/digit motor function was assessed using a modified dexterity board before and after the M1 and LPMC lesions in ten monkeys. We found a strong negative relationship between the degree of handedness and the recovery of manipulation skill, demonstrating that higher hand preference was associated with poorer recovery of hand fine motor function. We also observed that monkeys with larger lesions within M1 and LPMC had greater initial impairment of manipulation and poorer recovery of reaching skill. We conclude that monkeys with a stronger hand preference are likely to show poorer recovery of contralesional hand fine motor skill after isolated brain lesions affecting the lateral frontal motor areas. These data may be extended to suggest that humans who exhibit weak hand dominance, and perhaps individuals who use both hands for fine motor tasks, may have a more favorable potential for recovery after a unilateral stroke or brain injury affecting the lateral cortical motor areas than individuals with a high degree of hand dominance.  相似文献   
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Color Doppler ultrasound (US) with point-spectral analysis was performed on eight patients with postbiopsy renal transplant arteriovenous fistulas. Waveform analysis of the supplying artery documented decreased resistive indices in all cases and increased flow velocities in seven. The peak-systolic flow velocity in the arteries supplying the fistulas ranged from 55 to 180 cm/sec (mean, 92 cm/sec), while the range in normal arteries was 20-52 cm/sec (mean, 32 cm/sec). The resistive indices of the arteries supplying the fistulas ranged from 0.31 to 0.50 (mean, 0.45), while the resistive indices of the normal arteries ranged from 0.60 to 0.92 (mean, 0.74). Arterialization of the venous waveform from the draining vein was also documented in all cases. In six cases, the increased flow velocities resulted in increased color saturation toward white in the supplying artery (n = 2) or in both the artery and the draining vein (n = 4), which was detectable on the realtime image. In six cases, flow turbulence resulted in localized tissue vibration, which appeared as random color assignment in extravascular renal parenchyma adjacent to the fistula. Knowledge of these imaging and Doppler characteristics should aid in the identification of renal transplant arteriovenous fistulas with color Doppler US.  相似文献   
99.
Teenaged girls comprise the largest percentage of new cigarette smokers in the United States today. Factors contributing to smoking initiation include peer pressure, family and social influences, cigarette availability, and cigarette advertising. Because three-quarters of smokers become dependent on cigarettes by age 20, smoking prevention programs aimed at the adolescent population have great potential. The proposed program outlined is directed at girls 12 to 18 years of age in New York City. Among the objectives are increasing students' knowledge of the short- and long-term health effects of smoking and awareness of the social factors which lead to smoking. Participants would be taught social skills and behaviors which could help them to resist initiating smoking, by such activities as assertiveness training through role playing. Endurance sports activities would be emphasized while learning of the effects of smoking on physical conditioning. The costs of such a program are estimated, and classroom activities are outlined.  相似文献   
100.
Although a number of different reconstructive techniques have been described for the treatment of axillary skin defects, split-thickness skin grafting continues to be the most common surgical modality. Here, we present our recent experience of using split-thickness skin grafts together with negative-pressure dressings for the management of defects following wide surgical excision of severe hidradenitis suppurativa. This technique ensures complete skin-graft take whilst allowing full shoulder mobility, thereby minimising the undesirable sequelae associated with split-thickness skin grafting alone.  相似文献   
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